The below doses are based on scientific research, publications, traditional use, or expert opinion. Many herbs and supplements have not been thoroughly tested, and safety and effectiveness may not be proven. Brands may be made differently, with variable ingredients, even within the same brand. The below doses may not apply to all products. You should read product labels, and discuss doses with a qualified healthcare provider before starting therapy.
Adults (over 18 years old)
Studies have evaluated 0.1-80 milligrams of melatonin taken nightly by mouth for up to three years for a variety of conditions. Research suggests that quick-release melatonin may be more effective than sustained-release formulations for sleep-related conditions. Intramuscular injections of 20 milligrams of melatonin have also been studied.
In studies of patients with melanoma, melatonin preparations have been applied to the skin. Patients are advised to discuss cancer treatment plans with an oncologist and pharmacist before considering use of melatonin either alone or with other therapies. For the prevention of sunburn, melatonin preparations, alone and in combination with ascorbic acid and vitamin E, in doses ranging from 20-100 milligrams in 70% ethanol, have been studied.
Intranasal melatonin (1% solution in ethanol) at a dose of two milligrams daily for one week has also been studied for high blood pressure.
A dose of 0.5 milligrams of transbuccal melatonin for two sessions on four consecutive nights, at least three days apart, has been studied for insomnia in the elderly.
There are other uses with limited supportive research and unclear effectiveness or safety. Use of melatonin for any condition should be discussed with a primary healthcare provider, appropriate specialist, and pharmacist prior to starting, and it should not be substituted for more proven therapies.
Children (under 18 years old)
There is limited study of melatonin supplements in children, and its safety is not established. Doses of up to up to nine or 10 milligrams per kilogram of body weight, as a single dose or over several months, have been studied. Use of melatonin should be discussed with the child's physician and pharmacist prior to starting.